Do I need to even use blueprints?
Andrew Price did a tutorial on modeling a 747 where he used orthographic drawings of the plane as backgrounds in the scene and then modelled over the top of them.  The backgrounds can be associated with the view direction.  He also suggested in his tutorial a web repository of ortho drawings that you can goto for different vehicles.  I think the images were free, but I'm not sure.
Andrew goes through laying out and sizing background images, drawing over them and the other steps involved in constructing a model using this approach-which you see frequently in industrial design.
The advantage of this approach as opposed to just using reference images, is that it gives you dimensionally accurate references for laying out your meshes, eliminating a lot of the guesswork in determining sizes and proportions of elements in an object-especially if the camera angle and lens make those difficult to gauge.
As you gain experience and proficiency, you'll be able to rely on your memory more and incorporate your own ideas into the process.
Experts like Ron Cobb and Syd Meade can conjure incredible levels of detail and accuracy from their grey matter by virtue of being able to understand the interrelationships of geometry in their subjects and having exceptional control and discipline in their creative processes. So as to whether you can do well enough with reference images, I'd say that depends entirely on you and what you're trying to accomplish
But if you were a Syd Meade or Ronn Cob or John Laseter, you'd know it.  For the present, you should use the sketch layout (blueprint method) of modeling because it gives you the most opportunity to study how geometric shapes go together to create forms.
Where reference images really come in handy is in understanding the effects of light through different materials, how cameras and optical effects add impact and how composition creates drama in a scene.